The QuarterHorse plugs into the J3 port, like a chip module, on EEC-IV and EEC-V through 2004 Ford vehicles. Here are the key capabilities:

Datalogging of all sensors and values to the PC.

True real time emulation allows instant changes to any calibration parameter while engine is running.

Box reading for EEC-IV/V.

You can change ANY parameter while the vehicle is running without disturbing operation. You can log ANY parameter in RAM from the EEC-IV and V at sample rates well over 2,000 frames per second through the same mini USB cable (no OBD cable needed). Simultaneous ultra-high-speed rigorous datalogging capabilities are closely-coupled with the realtime-emulation/tuning-on-the-fly for the ultimate tuning experience. This device continues the tradition and heritage of our highly-integrated, low-cost, high-quality tuning tools from GM and Honda into the Ford arena. It requires Clint Garrity's Binary Editor Software available here.

It also supports reading of the EEC port to harvest 'stock' binaries. This must be done in-vehicle, or on a test bench harness, to supply the EEC with power.